Normal Vascular Anatomy (Arteries) Flashcards
This is the first vessel that arise from the aortic arch.
Innominate artery (IA), also known as the braciocephalic trunk
Shortly after its origin the IA bifurcates into the right subclavian and right common carotid arteries.
What are the major branches of the right subclavian artery (SCA)?
Vertebral artery
Internal mammary artery
Thyrocervical trunk
Costocervical trunk
At what level does the right CCA bifurcates into the external and internal carotid arteries?
At the midcervical level, typically around the C3 to C5 level
This is the second major vessel originating from the aortic arch.
Left common carotid artery
This is usually the last branch that arises from the aortic arch.
Left subclavian artery
What are the branches of the external carotid artery?
Superior thyroid artery Ascending pharyngeal artery Lingual artery Facial artery Occipital artery Posterior auricular artery Superficial temporal artery Internal maxillary artery
What are the extracranial segments of the internal carotid artery?
The first two segments: The carotid bulb and the cervical ICA
Segment of the ICA that includes the distal 2 to 4 cm of the CCA, the bulbous dilatation at the ICA origin, and a 2- to 4- cm segment beyond the bifurcation.
Carotid bulb
This segment of the ICA typically has neither narrowing or dilatations, almost never branches, and does not taoper.
Cervical segment
Segment of the ICA where it enters the carotid canal in the petrous temporal bone.
Petrous segment
Within the temporal bone the ICA first makes an anteromedial right angle bend, then bends again as it courses cephalad to enter the cavernous sinus.
An inconstant branch of the intrapetrous ICA that courses through the foramen lacerum and vidian canal to anatomose with branches of the ECA.
Vidian artery (artery of the pterygoid canal)
This segment of the ICA exits from the carotid canal at the petrous apex and terminates at its entrance into the intracranial subarachnoid space adjacent to the anterior clinoid process.
Cavernous segment
The cavernous ICA is further subdivided into 5 parts.
What are these parts?
Ascending cavernous portion (C5) - Extends from the endocranial opening of the carotid canal to the beginning of the first (posterio) ICA genu
Genu itself (C4), or the portion between ascending and horizontal segment
Horizontal portion (C3), lies between the posterior and anterior 90 degrees bends
Anterior genu portion (C2) - extends between the horizontal segment and remainder of the intracavernous ICA
C1 - remainder of the intracavernous ICA
Where does the opthalmic artery arises?
From the anterosuperior ICA medial to the anterior clinoid process.
Where does the posterior communicating artery arises?
From the posterior aspect of the intradural ICA just below the anterior choroidal artery
What vessels comprises the circle of Will?
- Two ICA
- The horizontal (A1) segments of both anterior cerebral arteries
- Anterior communicating artery
- Two posterior communicating arteries
- The horizontal (P1) segments of both posterior cerebral arteries
- Basilar artery
What are segments of the anterior cerebral arteries (ACA)?
Horizontal (A1) segment - The A1 segment extends medially from the ACA origin to its junction with the anterior communicating artery
Where does the medial lenticulostriate arteries arise?
A1 segment and pass cephalad through the anterior perforated substance
These small vessels usually supply the head of the caudate nucleus and anterior limb of the internal capsule.
This segment of the ACA includes the ACA from its junction with the ACoA to its bifurcation into the pericallosal and callosomarginal arteries.
A2 segment
Recurrent artery of Heubner is a lenticulostriate branch that typically arises where?
From the proximal A2 segment (50% of the case)
What are the two main terminal of the ACA branches?
Pericallosal and callosomarginal arteries (A3)
The middle cerebral arteries are divided into several major segments. What are these segments?
Horizontal (M1) segment
Insular (M2) segment
Opercular (M3) segment
This segment of the MCA extends laterally from its origin at the ICA bifurcation to its bifurcation or trifurcation at the sylvian fissure.
Horizontal (M1) segment
The lateral lenticulostriate arteries arise from where?
From M1 segment
It course superiorly to supply the lentiform nucleusm as well as part of the internal capsule and caudate nucleus.
These are the MCA branches as they emerge from the sylvian fissure and ramify over the hemispheric surface.
Opercular (M3) segments.
Where does the posterior cerebral arteries originate?
From the basilar artery bifurcation.
What are the major PCA segments and their branches?
Precommunicating (P1 or penduncular) segment
Ambient (P2) segment
Quadrigeminal (P3) segment
Posterior thalamoperforating arteries arise from where?
Arise from the basilar bifurcation and P1 segments
It then pass cephalad and dorsally to supply the diencephalon (thalamus) and midbrain.
The medial posterior choroidal artery originates where?
It originates either from P1 or the proximal P2 segment and runs anteromedially along the roof of the third ventricle.
It supplies the tectal (collicullar plate), part of the midbrain and posterior thalamus, pineal gland, tela choroidea of the third ventricle.
What part of the posterior cerebral artery supplies the medial geniculate body, pulvinar, brachium of the superior colliculus, crus cerebri, and occasionally, the lateral geniculate body.
Premesencephalic crucral (ambient, or P2) PCA segment
This PCA segment runs behind the midbrain within the quadrigeminal plate cistern.
Quadrigeminal (P3) segment
What artery supplies the posterior one-third of the interhemispheric surface in reciprocal relationship with the ACA branches.
Parietooccipital artery
This arteries supply the splenium of the corpus callosum and anastomose with their counterparts from the ACA.
Posterior pericallosal (splenial) arteries
The vertebral arteries (VA) usually originate from their respective subclavian arteries.
What vertebral artery is the dominant vessels?
Right or Left?
Left vertebral artery (50% to 60% of cases)
The VA course cephalad to entre the transverse forminana typically at what cervical level?
At C6
They ascend directly to C2 where they turn laterally, then superiorly , through the C1 vertebral foramina.
The posterior meningeal artery (PMA) arises where?
It usually arise from the VA as it courses along the posterior arch of the atlas.
The PMA supplies the falx cerebelli and can become greatly enlarged with dural vascular malformations or neoplasm.
The posterior inferior cerebellar artery (PICA) typically arises as a single trunk from the VA.
The PICA has the following five segments. What are these segments?
- An anterior medullary segment in front of the medulla
- A lateral medullary segment that courses alongside the medulla caudally to the level of CNs IX- XI
- A tonsillomedullary segment that courses around the inferior half of the cerebellar tonsil
- A telovelotonsillar segment in the cleft between the tela choroidea and inferior medullary velum rostrally and the superior pole of the tonsil caudally
- Cortical or hemispheric branches
What does the posterior inferior cerebellar artery supplies?
Choroid plexus of the fourth ventricle, posterolateral medulla, cerebellar tonsil, inferior vermis, and posteroinferior surface of the cerebellar hemisphere.
What is the first major branch of the basilar artery?
Anterior inferior cerebellar artery
This arteries arise near the basilar artery apex and curve posterolaterally around the pons and mesencephalon below the tentorial incisura and CNs III and IV.
Superior cerebellar arteries
These arteries supply the entire superior surface of the vermis and cerebellar hemispheres, as well as much of the deep cerebellar white matter and dentate nuclei.